Train Physics Problem

From	Fabian Russell <root@localhost.localdomain>
Newsgroups	sci.physics
Subject	Train Physics Problem
Date	2015-11-03 02:05 +0000
Organization	NewsGuy - Unlimited Usenet $23.95
Message-ID	<pan.2015.11.03.02.06.31@localhost.localdomain> (permalink)

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Attention physics enthusiasts:

In all of the information that I have encountered about train
physics -- and there is not a lot of material available -- the
energy required to move a train is calculated by considering
factors such a inertia (train mass), mechanical resistance (friction),
and air resistance (drag).

However, one significant factor is always ignored, and that is
the rotational energy of the wheel sets.

Why?  What is the reason for omitting the rotational energy?

In the US, a train wheel is very nearly 1 meter in diameter and
has a mass of 1000 kg.  The rotational energy for one wheel is
then 1/2 * I * w^2.  At 60 mph (27 m/s) speed, the energy is 179862 Joules.

At 4 wheel sets per car (8 wheels) with an average train containing
100 cars, the total rotational energy of the wheels is a whopping
143889600 Joules = 144 megajoules.

Yet this energy is ignored.

For a reference, see page 2 of this link:

http://s000.tinyupload.com/?file_id=07666111176590991515

This is a Microsoft Word (doc) file.

A LibreOffice (odt) version is here:

http://s000.tinyupload.com/?file_id=00684379287173743496

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Train Physics Problem Fabian Russell <root@localhost.localdomain> - 2015-11-03 02:05 +0000
  Re: Train Physics Problem Fabian Russell <root@localhost.localdomain> - 2015-11-03 02:31 +0000
    Re: Train Physics Problem Fabian Russell <root@localhost.localdomain> - 2015-11-03 02:38 +0000
    Re: Train Physics Problem gillyshin <spectrum8@sincity.info> - 2015-11-03 04:38 +0000
      Re: Train Physics Problem gilber34 <fafa@invalid.com> - 2015-11-02 22:58 -0600
        Re: Train Physics Problem Fabian Russell <root@localhost.localdomain> - 2015-11-03 05:22 +0000
  Re: Train Physics Problem Odd Bodkin <bodkinodd@gmail.com> - 2015-11-03 08:38 -0600
    Re: Train Physics Problem Fabian Russell <root@localhost.localdomain> - 2015-11-03 18:19 +0000
      Re: Train Physics Problem Odd Bodkin <bodkinodd@gmail.com> - 2015-11-03 15:00 -0600
        Re: Train Physics Problem Fabian Russell <root@localhost.localdomain> - 2015-11-03 21:22 +0000
          Re: Train Physics Problem Odd Bodkin <bodkinodd@gmail.com> - 2015-11-03 16:55 -0600
            Re: Train Physics Problem Fabian Russell <root@localhost.localdomain> - 2015-11-03 23:19 +0000
        Re: Train Physics Problem Fabian Russell <root@localhost.localdomain> - 2015-11-03 21:31 +0000
          Re: Train Physics Problem Odd Bodkin <bodkinodd@gmail.com> - 2015-11-03 17:17 -0600
    Re: Train Physics Problem benj <none@gmail.com> - 2015-11-03 13:41 -0500
      Re: Train Physics Problem Fabian Russell <root@localhost.localdomain> - 2015-11-03 18:53 +0000
        Re: Train Physics Problem benj <none@gmail.com> - 2015-11-04 18:08 -0500
          Re: Train Physics Problem Fabian Russell <root@localhost.localdomain> - 2015-11-04 23:33 +0000
      Re: Train Physics Problem Odd Bodkin <bodkinodd@gmail.com> - 2015-11-03 15:10 -0600
        Re: Train Physics Problem Fabian Russell <root@localhost.localdomain> - 2015-11-03 21:48 +0000
          Re: Train Physics Problem benj <nobody@gmail.com> - 2015-11-04 02:45 -0500
  Re: Train Physics Problem "reber g=emc^2" <herbertglazier0@gmail.com> - 2015-11-03 09:19 -0800
    Re: Train Physics Problem "reber g=emc^2" <herbertglazier0@gmail.com> - 2015-11-04 15:15 -0800

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